std::regex_constants::error_type

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Regular expressions library
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Defined in header <regex>
enum error_type {     error_collate = /*unspecified*/,     error_ctype = /*unspecified*/,     error_escape = /*unspecified*/,     error_brack = /*unspecified*/,     error_paren = /*unspecified*/,     error_brace = /*unspecified*/,     error_badbrace = /*unspecified*/,     error_range = /*unspecified*/,     error_space = /*unspecified*/,     error_badrepeat = /*unspecified*/,     error_complexity = /*unspecified*/,     error_stack = /*unspecified*/, };     constexpr error_type operator~(error_type f); constexpr error_type operator&(error_type lhs, error_type rhs); constexpr error_type operator|(error_type lhs, error_type rhs);

The error_type is a type that describes errors that may occur during regular expression parsing.

[edit] Constants

^ Value ^ Effect(s) if set ^ |error_collate|expression contains an invalid collating element name| |error_ctype|expression contains an invalid character class name| |error_escape|expression contains an invalid escaped character or a trailing escape| |error_backref|expression contains an invalid back reference| |error_brack|expression contains mismatched square brackets ([ and ])| |error_paren|expression contains mismatched parentheses (( and ))| |error_brace|expression contains mismatched curly braces ({ and })| |error_badbrace|expression contains an invalid range in a {} expression| |error_range|expression contains an invalid character range (e.g. [b-a])| |error_space|there was not enough memory to convert the expression into a finite state machine| |error_badrepeat|one of *?+{ was not preceded by a valid regular expression| |error_complexity|the complexity of an attempted match exceeded a predefined level| |error_stack|there was not enough memory to perform a match|

[edit] Operators

Bitwise operators ~, &, and | are also defined for error_type.